Siemens SIMATIC ET 200pro - Operating Modes of the CPU; STARTUP Mode

Commissioning
8.4 Operating modes of the CPU
CPU 1516pro-2 PN (6ES7516-2PN00-0AB0)
78 Operating Instructions, 11/2019, A5E35873416-AC
8.4 Operating modes of the CPU
8.4.1 Operating modes of the CPU
Introduction
Operating states describe the behavior of the CPU at a specific time. The following operating
states are possible via the mode selector:
● STARTUP
● RUN
● STOP
In these operating modes, the CPU can communicate, for example, via the PROFINET IO
interface (X1).
The status LEDs on the front side of the CPU indicate the current operating mode.
8.4.2 STARTUP mode
Response
Before the CPU starts to execute the cyclic user program, a startup routine is executed.
In the startup routine, you specify initialization tags for your cyclic program by programming
startup OBs. That is, you can set up one or several startup OBs in your program, or none at
all.